PROPRIETARY ANTIGEN EXPRESSION SYSTEM

Enhancing the visibility of specific target antigens and making them more widely recognized by a patient’s immune system is a critical aspect of effective vaccines. Marker’s PolyStart™ platform is a nucleic acid-based technology that increases the potency of vaccines by conferring a four-fold increase in expression of target-cell-specific, naturally processed antigenic epitopes on a cells surface. This enhanced antigen presentation boosts helper and/or long-lived killer T cells, which then effectively seek out and destroy target cells.

To do this, the proprietary PolyStart™ sequence (which contains a series of non-conventional translation start codons) is directly linked to a poly-antigen array (PAA) cassette encoding one or more antigens that correspond to the target molecule of interest. Translation of the protein product(s) initiates at each of the start codons, resulting in multiple translation products from a single template. These abundant translation products are then naturally processed through the proteasome and presented on the cell surface.

The data below demonstrate that the increased MHC class I-restricted antigen presentation driven by the PAA results in superior target recognition, when compared to peptide-pulsing of the same cells.

ENHANCED ANTIGEN EXPRESSION INCREASES FUNCTIONAL T CELL RESPONSES

PolyStart Graph_37

This proprietary technology was invented by TapImmune Inc. and is fully owned by Marker Therapeutics and has applications in immuno-oncology as well as other areas like infectious disease. It can be applied to the company’s current T cell vaccine candidates, as well as drive incremental value for Marker through strategic out-licensing and/or collaboration with other companies.